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211.
Not only is the carbon market inundated with Certified Emissions Reductions (CERs) issued by successful projects, it is also littered with failed projects, that is, projects that either fail to be registered under the Clean Development Mechanism (CDM) or projects that have been successfully registered but fail to issue CERs. By relying on a novel application of survival analysis in the context of the CDM, this article shows that half of all projects that start the Global Stakeholder Process fail to issue CERs, while the other half have a median time to market of four years. Furthermore, it is shown that some of the best projects, in terms of being additional, are those that are least likely to make it to market, whereas some of the worst projects, in terms of not being additional, are the ones that are most likely to make it to market. This presents a fundamental challenge for the CDM and future offset schemes that rely on the same design as the CDM. In contrast with previous studies, it is shown that, when project characteristics are controlled for, not all durations measured along the CDM project cycle have increased over time.

Policy relevance

This article develops a novel method for analysing durations measured along the CDM project cycle that avoids the biases of previous studies, and corrects for some misconceptions of what the delays faced by CDM projects are and how these delays have changed over time. Developing an understanding of the delays is important in order not to draw the wrong lessons from the CDM experience. As the leading example of an offset scheme, both in terms of geographical scope and sectoral coverage, and some would say institutional complexity, the CDM serves as a benchmark and reference for all future offset schemes, among others, for the New Market Mechanisms (NMMs) and the Chinese domestic offset programme. While the NMMs are still very much in development, China has announced that it will rely on the methodologies and procedures developed under the CDM for generating offsets for their regional carbon trading schemes.  相似文献   
212.
Technology transfer (TT) is not mandatory for Clean Development Mechanism (CDM) projects, yet proponents of CDM argue that TT in CDM can bring new technologies to developing countries and thus not only reduce emissions but also foster development. We review the quantitative literature on determinants of TT in CDM and estimate determinants for CDM projects in China. China is by far the largest host country of CDM projects and it is therefore crucial to understand the factors that drive TT there. To gain better interpretation, we focus on heterogeneity within a single country and results can thus be linked to specific policies of the country. Our probit estimations confirm previous international cross-country studies, indicating that larger projects and more advanced technologies are more likely to involve TT. In addition, we find evidence that agglomeration effects are more pronounced at the province level rather than larger regions. We also find a positive effect of foreign direct investment (FDI) on TT, and academic research and development (R&D) is complementary to TT.

Policy relevance

Technology transfer (TT) is a goal of Chinese CDM legislation, but it is not a prerequisite for project approval. Our estimations show the project specific, technological and region-specific features that encourage more TT among CDM projects. Some variables analysed such as R&D spending and FDI (both are found to have positive effects on TT) can be, to some extent, influenced by the policy-makers. Moreover, we find some evidence for the presence of negative agglomeration effects on the provincial level: the likelihood of TT is decreasing in the number of previous projects operating in the same technology and province. This finding needs to be interpreted with great caution. It may suggest the existence of a learning externality, which could serve as a justification for policy intervention. Any policy intervention requires however careful analysis of potential positive or negative externalities resulting from the agglomeration of CDM projects and a comparison of possible benefits with the costs of TT.  相似文献   
213.
The objective of this paper is to assess recent developments and prospects for future changes in United States (US) climate strategy. In doing so, the paper explores some of the key factors that have shaped strategies and policies to date, distinguishing between factors related to institutional and governance structures, linkages between science and policy, energy technology and the role of interest groups. Against this background, the paper attempts to explore future development paths for US climate policy. More specifically, the paper assesses opportunities for policy changes compared to the preferences of the current administration, and the prospects for future linkages between US and international climate change strategies. In brief, the paper argues that substantial changes are unlikely to take place in the near to medium term, leaving open, however, the possibility of wide-ranging changes in domestic politics or major incidents that could facilitate a shift in the perceived need for near-term action.  相似文献   
214.
辽宁省辽河流域水污染防治政策与机制的探讨   总被引:2,自引:2,他引:2       下载免费PDF全文
基于辽宁省辽河流域水环境安全的严峻形势,从产业结构调整与经济布局、环境资源价值、环保投入机制3个方面对造成辽宁省辽河流域水环境问题的主要原因进行了分析,并对现阶段辽宁省辽河流域水污染防治的相关政策与合理机制进行了深入探寻,试图为辽河流域水污染防治的可持续管理提供参考依据。  相似文献   
215.
张苏平  王媛  衣立  刘海坤  王倩 《大气科学》2017,41(2):227-235
由于缺乏海上现场观测,对天气尺度扰动下,海表面温度锋 (海洋锋) 对海洋大气边界层 (MABL) 垂直结构和MABL内海洋性低云 (marine stratus) 的影响研究较少。2014年4月12日,中国海洋大学东方红2号科学考察船在黑潮延伸体海区的海洋锋附近捕捉到一次层积云的迅速发展。在比较稳定的天气形势下,由暖水侧向北穿越海洋锋时,云底和云顶高度升高,云区范围迅速扩大。本文利用多种大气-海洋联合观测数据,结合卫星观测和再分析资料,对此次层积云迅速发展的机理进行了综合分析。结果表明,在海上低压后部西北风控制下,在海洋锋的暖水侧 (下风方) 形成热通量大值中心和低压槽,有助于高空西风动量下传,进而又使得海气界面热通量增加,这种正反馈效应为MABL内混合层厚度加大和云底/顶高度在海洋锋的下风方升高提供有利背景条件。4月12日09:00~12:00(协调世界时),来自日本本州岛陆地的低空暖平流到达该热通量中心上空,暖平流与热通量中心的共同作用,导致该时段近海面暖中心强度异常增加,MABL中静力不稳定层加深和低压槽发展,综合作用的结果使得混合层厚度明显加深,云底高度升高,云区迅速发展。本研究有助于理解在复杂大气背景扰动下MABL对海洋强迫的响应机理。  相似文献   
216.
气溶胶影响云和降水的机理和观测研究进展   总被引:2,自引:3,他引:2  
李军霞  银燕  李培仁  徐芬 《气象科学》2014,34(5):581-590
气溶胶对云和降水的影响,对于气候系统、大气环境以及水循环至关重要。气溶胶粒子作为云凝结核和大气冰核影响云的微物理过程,进而影响雨、雪、雹和其他形式的降水。近年来,在理解气溶胶的化学成分,气溶胶微物理特性以及气溶胶作为云凝结核和大气冰核影响云降水等方面已取得重大进展。本文对于气溶胶的概念、来源以及气溶胶的直接和间接效应进行了简要概述,重点总结了国内外在气溶胶影响云和降水的机理研究方面的成果,回顾了近年来利用卫星、地面观测设备、机载探测设备等对气溶胶和云进行遥感观测和直接观测所获得的观测事实并讨论了其可能的物理机制,在总结前人研究成果的基础上对未来的研究方向进行了讨论。  相似文献   
217.
我国暴雨形成机理及预报方法研究进展   总被引:3,自引:0,他引:3  
本文分别从华南前汛期暴雨、江淮流域梅雨锋暴雨、华北和东北暴雨以及暴雨预报方法等方面回顾了我国近年来在三大主要雨带的观测、数值模拟、动力机理及诊断分析和预报方法方面取得的进展,指出了华南前汛期暴雨、江淮梅雨锋暴雨及华北东北暴雨研究取得的新认识,认为华南前汛期暴雨的形成机理主要是发生在低空南风向北推进过程中,由海岸线及地形抬升而产生位势不稳定造成强上升运动,以及由于南风低空急流向北发展时产生急流前部的辐合而发生流线分叉使低层低涡发展,促进垂直运动加强或使正涡度集中促使垂直运动发展而造成暴雨;江淮暴雨生成机制主要与对称不稳定、涡度场变化及β中尺度对流线有关;而华北东北暴雨过程中的非均匀饱和引起的局部湿度集中特点较为明显,中高层干冷空气入侵引起的不稳定和动量下传及高空中尺度急流增强引发的高层局地辐散增强对暴雨发生有重要作用。目前,新型探测资料已经用到暴雨研究和预报中,具有自主知识产权的GRAPES-MESO和GRAPES-GFS系统已经实现业务化,并在集合数值预报方面取得显著进步,且动力因子暴雨预报方法在很多省市气象台得到推广应用。虽然暴雨机理研究和预报已经取得以上诸方面的长足进步,但是也还存在不少问题,需要加强基于观测的暴雨中尺度系统的理论研究、数值模式动力框架和物理过程描述的改进、资料同化理论技术的发展及人工智能技术如何用到大气科学的研究和业务应用等,以期在我国暴雨中尺度系统的三维精细结构、发生发展机理和预报理论和方法研究方面取得更大进步。  相似文献   
218.
Moment tensor solutions were retrieved for the earthquake swarm that occurred during November and December 2010 in the Boshan mining area, Shandong Province, China. The results showed that the double-couple components in the source mechanisms were higher at the beginning of the swarm and consisted mainly of shear faulting controlled by tectonic stress. The subsequent events had significant non-double-couple components, indicating tensile faulting. The double-couple components predominately presented as normal faulting and the P axes were orientated almost vertically. The slip vectors of the swarm events were relatively stable. With reference to the tectonic features near the epicenter, we concluded that the swarm was a result of subordinate fault motion related to the Wangmu Mountain fault and that high-pressure pore fluids played a crucial role in the activity of the earthquake swarm.  相似文献   
219.
石油二次运移优势路径形成过程实验及机理分析   总被引:18,自引:2,他引:18       下载免费PDF全文
利用填装玻璃微珠的玻璃管模型,观察静水条件下油在饱含水孔隙介质中靠浮力形成优势运移路径,以及随后沿已形成的路径运移的过程。实验发现,运移的形成过程、路径的形态以及油在已形成的路径内的运移均表现出强烈的非均一性;前缘跳跃、分段运移等现象揭示了运移过程的复杂性。运移路径一旦形成,直到运移结束,其形态和空间展布特征基本一致;再次注入的油仍基本沿原来的路径运移。连续油柱的浮力及该连续油柱所接触到的孔道的毛细管力之间的复杂关系决定了油气非均匀运移路径的形成过程及其形态特征。  相似文献   
220.
粘弹性数值模拟龙门山断裂带应力积累及大震复发周期   总被引:4,自引:0,他引:4  
柳畅  朱伯靖  石耀霖 《地质学报》2012,86(1):157-169
2008年5月12日在低地形变速率的龙门山断裂带上突发汶川强震,引发人们对该地震孕震机制的思考。本文根据GPS观测资料确定边界条件,通过三维粘弹性数值模拟探讨了汶川地震的孕震机理,计算了该区域岩石圈的应力增加速率和积累过程,以及汶川地震同震应力变化与震后应力松弛,在此基础上估算了汶川8.0级大地震的复发周期。数值模拟结果表明:印度板块对欧亚板块的推挤造成青藏高原的物质东流,高原中、下地壳物质在龙门山断裂带处遭到相对坚硬的四川盆地的阻挡之后,部分中、下地壳物质在龙门山断裂带下堆积产生应力集中。两个重要因素为应力集中提供了重要控制作用:其一是青藏高原中、下地壳较低的粘滞系数与四川盆地中、下地壳较高的粘滞系数的差异,其二是从青藏高原到四川盆地的Moho面深度在龙门山断裂带的突变。低应变速率的龙门断裂带岩石圈在数千年时间尺度的应力积累过程中,脆性上地壳的应力随时间近乎线性增长,并且上地壳深部的应力增长率超过浅部,6000年内应力积累最大量达到-21.6MPa,应力增长速率为-0.0036MPa/a;而柔性的中、下地壳以及岩石圈上地幔的应力在增长一段时间之后趋于稳定。在空间上,龙门山断裂带受到的压应力从断层西南向北东方向逐渐减小,而剪应力从西南到北东方向逐渐增大,应力状态有利于地震发生时断层的破裂方式从西南的逆冲运动向北东的逆冲兼走滑运动的方式发展。通过应力积累与地震应力降的计算得到汶川8.0级大地震的复发周期约为5400年。  相似文献   
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